Ion Selective Electrochemical Sensors—Fe+3, Cu+2

Ion selective electrochemical sensors which respond to Fe +3 and Cu +2 have been developed. The sensor material consists of a chalcogenide glass (60% Se, 28% Ge, and 12% Sb) doped with Fe 0 , Co 0 , or Ni 0 . Response has been observed at concentrations as low as 10 −6 moles/liter (0.056 ppm Fe) in both membrane and electrode configurations. Nernstian behavior is observed in the 10 −5 to 10 −1 moles/liter concentration range. Interference tests demonstrate good selectivity for Fe +3 in the presence of most cations, particularly Fe +2 . Potential response behavior supports a redox potential mechanism rather than the ion exchange mechanism.